Why do fence gates sag over time?

Gates sag because they are heavy, cantilevered panels supported only at the hinge side. Over time, the weight pulls the latch corner down — loosening hinge screws, pulling the hinge post out of plumb, or racking the gate frame itself. Wood moisture cycles also cause expansion and contraction that works hinge fasteners loose. Most gate sag is fixable without replacing the gate.

What is a gate tension rod and how does it fix a sagging gate?

A gate tension rod (also called a gate anti-sag kit or turnbuckle rod) is a steel cable or rod that runs diagonally across the back of the gate frame from the top hinge corner to the bottom latch corner. Tightening the turnbuckle in the middle of the rod pulls the low corner up, counteracting sag. This is the most effective long-term fix for wood gate sag and costs about $15–$25 for a complete kit.

My gate hits the ground when I open it. Do I need to replace the post?

Not necessarily. First check whether the gate itself has sagged (the latch corner drops as you open it) — a tension rod or hinge adjustment fixes this without touching the post. If the post leans away from the gate, the post footing has failed and the post needs to be reset. If the ground beneath the gate has heaved or the grade has changed, you may be able to trim the gate bottom instead.

How do I tighten loose gate hinges?

If the hinge screws spin freely, the wood has stripped out. Remove the hinge, pack the screw holes with toothpicks and wood glue, let cure overnight, then reinstall the hinge. For gate hinges (which bear more load than cabinet hinges), also consider upgrading to longer, heavier lag screws if the gate lumber is thick enough. Through-bolting the hinge with carriage bolts is the strongest option.

What size hinges do I need for a fence gate?

A standard 4-foot wide wood gate weighing 30–50 pounds needs at least two strap hinges or butt hinges rated for the gate weight — typically 6-inch or 8-inch heavy-duty gate hinges. Heavier gates (double gates, arched gates, wide gates) need three hinges or heavy-duty 10-inch weld-on hinges rated for the load. Never use lightweight interior-style hinges on an exterior gate.

My gate latch no longer lines up with the post. How do I fix it?

Gate latch misalignment is almost always caused by the gate itself sagging or the latch post shifting. Fix the underlying sag or post lean first. Once the gate is back to its proper position, the latch should realign. If there is still minor misalignment after straightening, most gate latches have adjustable catch plates that can be repositioned on the post by 1/2 to 1 inch to match the latch bolt.

How to Repair a Fence Gate: Step-by-Step Guide

A sagging or sticking fence gate is one of the most common outdoor repairs.

A sagging or sticking fence gate is one of the most common outdoor repairs. In most cases the gate frame is fine — it just needs hinge tightening, a tension rod, or an adjustment to the latch hardware.

What You Need

Flathead and Phillips screwdrivers
Drill with driver bits
Anti-sag gate kit with turnbuckle and cable
Heavy-duty gate hinges (if replacing damaged hinges)
Lag screws or carriage bolts (upgrade from original screws if needed)
Level
Wrench or ratchet set
Wood shims or scrap lumber (for propping the gate while working)

Step 1: Diagnose the Problem

Open the gate and observe:

Gate drags on the ground at the latch corner — the gate is sagging. Check whether the hinges are loose or the gate frame has racked.
Gate won’t latch — either the gate has sagged, the latch post has shifted, or the latch hardware is worn.
Gate sticks or is hard to open — post is out of plumb or the gate has swelled.
Hinge knuckles are bent or broken — hardware replacement needed.

Use a level on the hinge post to check if it is plumb. Check the gate frame for square by measuring diagonally corner to corner — if the two diagonal measurements differ, the frame has racked.

Step 2: Tighten or Replace the Hinges

Prop the gate up to its correct open position using scrap lumber under the latch corner. With the gate supported, check every hinge screw. Tighten any that are loose.

If screws spin freely (stripped holes), remove the hinge and pack the holes with toothpicks dipped in wood glue. Let cure overnight. Reinstall the hinge and drive new screws — or upgrade to longer 3-inch lag screws for a stronger bite.

If the hinge leaves are bent or the knuckles are damaged, replace the hinges entirely. Bring the old hardware to the hardware store to match the size and weight rating.

Step 3: Install an Anti-Sag Tension Rod

An anti-sag kit corrects gate sag without replacing the gate or post. It works by pulling the low corner back up.

Installation:

Attach the top bracket to the top rail near the hinge side of the gate
Attach the bottom bracket to the bottom rail near the latch side of the gate
Run the cable or rod diagonally between the two brackets
Thread the turnbuckle into the cable and begin tightening — clockwise shortens the rod and pulls the latch corner up
Check the gate with a level as you tighten — stop when the top rail is level and the gate swings freely without dragging

Step 4: Adjust or Replace the Latch

Once the gate is back in position, test the latch. If the latch bolt does not reach the catch plate:

Loosen the catch plate screws and move the plate closer to the latch bolt
If the gap is large, add a shim behind the catch plate to bring it forward
Replace a corroded or broken latch with a matching heavy-duty exterior gate latch

Step 5: Treat and Protect

If any bare wood is exposed from drilling or replacing hardware, apply exterior wood sealer or paint to prevent moisture entry. Check the hinge post at ground level for rot — press a screwdriver into the wood at the soil line. Soft, punky wood means the post needs replacement before the gate repair is worthwhile.

Lubricate all hinge knuckles and latch mechanisms with a spray lubricant each spring to prevent corrosion and sticking.

How to Build a Fence — full fence installation from post setting to top rail
How to Fix a Leaning Fence Post — post repair when the gate post has shifted
Annual Home Maintenance Schedule — fence and gate inspection checklist

⏰ PT8H 💰 $10–$50 🔧 Pressure-treated lumber, Exterior screws or nails, Post hole digger, Concrete mix, Exterior wood sealer or stain

Diagnose the Problem
Gate drags on the ground at the latch corner — the gate is sagging. Check whether the hinges are loose or the gate frame has racked.
Tighten or Replace the Hinges
Prop the gate up to its correct open position using scrap lumber under the latch corner. With the gate supported, check every hinge screw. Tighten any that are loose.
Install an Anti-Sag Tension Rod
An anti-sag kit corrects gate sag without replacing the gate or post. It works by pulling the low corner back up.
Adjust or Replace the Latch
Once the gate is back in position, test the latch. If the latch bolt does not reach the catch plate:
Treat and Protect
If any bare wood is exposed from drilling or replacing hardware, apply exterior wood sealer or paint to prevent moisture entry. Check the hinge post at ground level for rot — press a screwdriver into the wood at the soil line.

How to Repair a Fence Gate: Step-by-Step Guide

What You Need

Step 1: Diagnose the Problem

Step 2: Tighten or Replace the Hinges

Step 3: Install an Anti-Sag Tension Rod

Step 4: Adjust or Replace the Latch

Step 5: Treat and Protect

Free: 10-Point Home Maintenance Checklist

Save this for next time.

How to Repair a Fence Gate: Step-by-Step Guide

What You Need

Step 1: Diagnose the Problem

Step 2: Tighten or Replace the Hinges

Step 3: Install an Anti-Sag Tension Rod

Step 4: Adjust or Replace the Latch

Step 5: Treat and Protect

Related Guides

Free: 10-Point Home Maintenance Checklist

Save this for next time.